This invention relates to a container or vessel and a blow molded article. More particularly it relates to a container used as a container for which a highly reduced solubility is required, such as a container for storage and transportation of a chemical liquid used for the production of a semiconductor.
For a chemical liquid of a high purity such as that used for the production of a semiconductor, it is required that it is not contaminated with as impurity or other foreign matters, and a high purity must be maintained during storage and transportation. Conventional containers for storage and transportation of a chemical liquid of a high purity were made of polyethylene, polypropylene or similar material. However, low-molecular-weight organic matter and trace amounts of metal elements are sometimes dissolved from polyethylene and polypropylene into the chemical liquid to reduce the purity to undesirable extent.
Thermoplastic cycloolefin reins such as a norbornene polymer era known as having good characteristics such as reduced solubility and high chemical resistance, and therefore, have been proposed for use in vessels or containers for medicines and food.
For example, a blow molded container having a capacity of 200 ml made of a double-layer laminate comprising a ring-opened norbornene polymer layer and a polycarbonate layer is described in Japanese Unexamined Patent Publication No. H4-276253. A container having a capacity of approximately 200 ml made from a thermoplastic norbornene resin by an injection blow molding procedure is described in Japanese Unexamined Patent Publication No. H10-157719.
Vessels for a chemical liquid used for treating a semiconductor usually have a capacity of several tens of liters and are required to be lightweight for transportation. Therefore, a molding material suitable for containers with a large capacity and a thin-wall having high mechanical strength is eagerly desired.
In view of the foregoing, a primary object of the present invention is to provide a container and a blow molded article, which exhibit a reduced solubility and even when the wall-thickness is reduced for fabrication of large-size containers or molded articles, high strength is manifested.
Thus, in accordance with the present invention, there is provided a container comprised of a laminate having (I) a layer comprising a thermoplastic cycloolefin resin and (II) a layer comprising a resin other than the thermoplastic cycloolefin resin, characterized in that said thermoplastic cycloolefin resin comprises at least 30% by weight of repeating units (A) having an alicyclic structure, at least 10% by weight of which is repeating units (A-i) having an alicyclic structure ether than a norbornane structure.